1. Field of the Invention
This invention relates to a fluid pump powered by a canned electric motor, and more particularly, to a canned electric motor having a removable stator cartridge.
2. Background Information
Pumps powered by canned electric motors are used in a variety of applications. For example, such pumps may be used to circulate cooling water through nuclear reactors. Pumps used in those types of applications are typically large and are powered by large motors. Often, the pump motors are positioned in confined spaces where ventilation for air cooling is poor. In such instances, adequate liquid cooling of the motor is necessary to reduce the build up of excess heat in the confined area. Circulation of cooling fluid around the stator, including between the stator and the pressure housing of the motor, is desirable for adequate cooling. With prior art canned motors, the stator is integral with the pressure housing. Thus, cooling fluid cannot circulate between the housing and the stator.
In addition, with motors of that configuration, the stator is not removable from the remainder of the motor without also removing the pressure housing. Thus, if the stator fails, it is often expedient to simply replace the entire motor rather than trying to replace the stator/pressure housing when the motor is in place. That approach requires that replacement motors be kept available in the event that maintenance is required.
Furthermore, when it is desirable to clean the stator, such as when the motor is operated in hazardous or corrosive conditions, that task is extremely difficult with prior art canned pump motors. Again, the entire pressure housing and stator cartridge must be removed, which typically requires removal and disassembly of the entire motor.
There is a need for a canned pump motor that has a stator that is separate and removable from the remainder of the motor and pump without requiring removal of the entire motor from the pump. There also remains a need for a canned pump motor that enables cooling fluid to be circulated between the shator and the pressure housing of the motor.